The present invention relates to a front body structure of a vehicle (such as a xe2x80x9ccarxe2x80x9d) in which an impact energy generated during a crash can be absorbed effectively by a front bulkhead, therefore promoting passenger safety. More particularly, the present invention relates to the front body structure in which wiper units are arranged on the front bulkhead such that the wiper units do not interfere with a collapse of the front bulkhead during a collision.
In the related art, such as disclosed in a Japanese Patent Unexamined Publication No. Hei. 9-95261, a front bulkhead is arranged along a lower edge portion of front windshield of a vehicle in a widthwise direction thereof so as to partition an engine room from a passenger compartment. In addition, a concave portion is opened upwardly and formed in the front bulkhead. A wiper unit is provided in the concave portion.
As the wiper unit, a modular wiper unit disclosed in Japanese Utility Model Examined Publication No. Hei. 8-6641, for example, is often employed. In the wiper unit of this type, in many cases a motor bracket used to fix the wiper motor to the front bulkhead is fixed to the inside of the concave portion of the bulkhead such that the motor bracket extends in the longitudinal direction of the vehicle.
However, when the vehicle collides head-on with an obstacle in front of the vehicle as the vehicle is moving forward, often at a high speed (referred to as the xe2x80x9cfrontal crashxe2x80x9d hereinafter), naturally, a large impact load (shock) is applied to a vehicle body from a front side. Then, the impact energy generated at that time is transmitted to a rear side of the vehicle via a front portion of the vehicle. In response, respective constituent parts provided in the front portion of the body are plastically deformed to absorb the impact energy.
Of course, if the impact load is transmitted to the bulkhead, the bulkhead is crashed to absorb the impact energy, so that an impact energy transmission into the compartment is reduced.
However, in a structure disclosed in the above Publication, since the motor bracket is fixed to the concave portion of the bulkhead such that the motor bracket extends in the longitudinal direction, the motor bracket acts inevitably as a reinforcement to the bulkhead. In addition, since the wiper motor is arranged at a lower position than that of upper surfaces of a strut towers that are arranged on both right and left sides of the front bulkhead, the wiper motor interferes with retreating strut towers to disturb the crash of the bulkhead. For this reason, the portion of the bulkhead to which the wiper motor is arranged becomes difficult to be locally crashed. Thus, there is a disadvantage in that the effect of absorbing the impact energy generated by the deformation of the bulkhead cannot be sufficiently achieved.
Also, since the wiper motor has a rigid body, a large reaction force is generated by the wiper motor when the impact load is applied to the wiper motor from the upper side of the vehicle. Therefore, the structure of the related art is less than ideal for reducing or eliminating the transmission of the impact energy to the passenger compartment.
The present invention has been made in view of above circumstances, and it is an object of the present invention to provide a front body structure of a vehicle that can effectively absorb an impact energy which is transmitted to a rear side of the vehicle, by accelerating a crash of a bulkhead by an impact load applied during a collision of the vehicle. Thus, the present invention is for effectively protecting passengers from an impact applied during the collision, and also for absorbing the impact energy to prevent a generation of a large reaction force even when the impact load is applied to a wiper motor from an upper side of the vehicle body.
In order to achieve the above object, the present invention provides a body structure of the vehicle comprising the bulkhead including a concave portion opened upwardly. The concave portion has front and rear wall surfaces and a wiper unit having a wiper motor is disposed between the front and rear wall surfaces of the concave portion. Further, the wiper motor is also disposed at a higher position than that of upper surfaces of strut towers of the vehicle.
According to such structure, the strut towers are moved toward the rear side of the vehicle by the impact energy at the time of the frontal crash to push the bulkhead. At this time, since the wiper motor is arranged at the higher position than that of the upper surfaces of the strut towers, such retreating strut towers can accelerate the crash of the bulkhead toward the rear side of the vehicle without an interference from the wiper motor.
In this case, preferably the wiper motor is fixed to the front bulkhead via a motor bracket, an inclined portion of which is bent downwardly and formed in front of the wiper motor. A lower end of the inclined portion is fixed to a front portion of the concave portion of the front bulkhead, and a weakening portion is provided in the inclined portion. Therefore, the crash of the bulkhead toward the rear side of the vehicle by the frontal crash can be accelerated even further. Also, the motor bracket can be easily broken if the impact load is applied to the wiper motor from the upper side of the vehicle. As a result, the impact energy can be absorbed effectively.